Pioneer PDP-4280HD, Руководство по обслуживанию

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PDP-4280HD
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1 2 3 4
1 2 3 4
C
D
F
A
B
E
8.5 ADJUSTMENT WHEN THE DRIVE ASSYS ARE REPLACED
TIME LAG ADJUSTMENT OF THE CONTROL SIGNAL (SUS-B)
1
Measure the time lag for the SUS-U signal to the SUS-B signal.
2
Check the time lag for the SUS-B GATE signal to the SUS-U GATE siganl.
Adjust the variable control so that the time lag of GATE becomes " time lag of input
α ±
5 nsec."
Note: For details on measuring points of waveform, see the figure below.
50 % of the crest value
5 V position
5 V position
Time lag of SUS-U Gate and SUS-B Gate :
Δ
Tsus - gub
Adjust so that "
Δ
Tsus - gub =
Δ
Tsus - iub +
α ±
5 nsec," using the variable
controls shown in the table below:
SUS-U signal (input to the DRIVE Assy)
SUS-B signal (input to the DRIVE Assy)
SUS-U Gate signal
SUS-B Gate signal
X DRIVE (GATE terminal of Q1210)
Y DRIVE (GATE terminal of Q2210)
X DRIVE (GATE terminal of Q1109)
Y DRIVE (GATE terminal of Q2107)
50 % of the crest value
time lag of SUS-U and SUS-B
Δ
Tsus-iub
time lag of SUS-U Gate and SUS-B Gate
Δ
Tsus - gub
Assy VR Value of
α
X DRIVE Assy
VR1002 70 nsec
Y DRIVE Assy VR2002 50 nsec
Waveform adjustments required when replacing the following parts of the X DRIVE and Y DRIVE Assys.
Assy Name Ref No. Part Name Part Category Remarks
X DRIVE Assy IC1101 PS9117AP Photo Coupler
IC1104 TND307TD FET Driver
IC1204 PS9117AP Photo Coupler
IC1209 TND307TD FET Driver
Y DRIVE Assy
IC2101 PS9117AP Photo Coupler
IC2103 TND307TD FET Driver
IC2201 PS9117AP Photo Coupler
IC2203 TND307TD FET Driver